The present invention makes use of a universal tank lid fabricated with multiple vents for use in instances when an ink tank is full of ink and when an ink tank is partially filled with ink. More specifically, supply side items such as ink tanks or ink cartridges must be periodically replaced after the inkjet printer deposits a predetermined volume of ink onto a print medium. Ink from these replaceable or refillable cartridges supplies the inkjet nozzles of the printhead so that continued printing is contingent upon a sufficient supply of ink.
Those skilled in the art are well aware that original equipment manufacturers (OEMs) of inkjet printers typically include starter ink tanks. These starter ink tanks are generally not filled to capacity with ink, but do provide the requisite ink to allow the purchaser to operate the printer and become familiar with the operations of the printer. One of the principal operations is the replacement of ink tanks as the ink is consumed. Another operation may include acclimating the purchaser/user with data readouts from the hardware indicating that the tank is low on ink and replacement will be required soon. This gives the purchaser the opportunity to see firsthand how many pages can be printed using a partially empty ink tank.
OEMs that supply replacement ink tanks and other ink tank manufacturers are constantly looking to reduce costs and complexity by making ink tanks and associated ink tank parts interchangeable and adaptable to meet a various operating conditions. As discussed above, one situation may include a starter tank having a substantial volume occupied by gaseous species. Contrast this situation to a replacement ink tank where the overwhelming majority of available volume internally is occupied by capillary producing material and liquid ink. The gaseous species present in starter tanks can be very problematic, especially during shipment. The reason is relatively simple: gases expand and contract much more than solids and liquids when exposed to temperature and pressure changes.
Shipping procedures can include air travel at relatively low pressures and low temperatures. This can cause the gases within the ink tanks to expand by 50% or more. If this degree of expansion were to take place in a fixed volume, the housing holding the gases and liquid ink would be greatly stressed and tend to bow outward to accommodate the expansion of the gases. One way to overcome this potential problem is to fill the ink tank completely full, thereby leaving little to no gaseous volume. A second option, which is encompassed by the instant invention, is to include a second vent allowing gases within the tank to communicate with an environment external to the tank, thereby accommodating for expansion and contraction by substantially maintaining a pressure balance between the interior of the tank and the external environment.
Ink tanks generally include two different configurations. A first configuration includes a single chamber that is occupied by a capillary producing material. A second configuration includes multiple chambers in communication with one another, where the chamber in direct communication with an outlet port includes the capillary producing material. This latter configuration in some circumstances is advantageous over the single chamber configuration because it allows more volume to be occupied by ink, commonly referred to as free ink chambers. Another advantage stems from sensor technology that more easily and accurately detects the amount of ink within a free ink tank than within a ink tank occupied by a capillary producing material.
The instant invention includes ink tanks having multiple chambers such as those having one chamber that is a free ink chamber in communication with a felt chamber that includes a capillary producing material at least partially saturated with liquid ink. The invention adopts a universal ink tank cap that can accommodate replacement situations where both the free ink chamber and the felt chamber are at least substantially full of ink, and a starter ink tank where the free ink chamber is virtually empty and the felt chamber is the primary source of ink to the printhead.
In some embodiments, an ink reservoir is described that comprises (a) a tank body; and (b) a tank cap mounted to the tank body and cooperating with the tank body to define a free ink chamber and a felt chamber for housing a liquid ink therein, the free ink chamber being in direct fluid communication with the felt chamber via an opening in a partition wall, the tank cap including a free ink vent in communication with the free ink chamber, and the tank cap further including a felt chamber vent in communication with the felt chamber.
In some embodiments, at least one of the free ink chamber vent and the felt chamber vent includes an ink fill port. In yet another embodiment, an underside of the ink tank cap includes a furrow adapted to receive the partition wall of the tank body. In a further embodiment, at least one of the free ink vent and the felt chamber vent includes a labyrinth duct having a length to width ratio of 25:1 or larger. In still another embodiment, the felt chamber includes a capillary producing medium for dispensing liquid ink from the felt chamber. In another embodiment, the free ink chamber is substantially free of a capillary producing medium. In yet another embodiment, a stop is included to inhibit direct communication between the free ink chamber and an external environment.
In still another embodiment, the felt chamber vent includes a felt chamber groove formed within the ink cap. In another embodiment, the free ink chamber vent includes a free ink chamber groove formed within the ink cap. In a further detailed embodiment, the tank cap includes a felt chamber vent through hole and a free ink chamber vent through hole. In still a further detailed embodiment, the tank cap further includes a covering substantially overlaying the felt chamber groove, the free ink chamber groove, the felt chamber vent through hole, and the free ink chamber vent through hole. In a another embodiment, the covering cooperates with the felt chamber groove to form a felt chamber duct with one end open to the felt chamber through hole and an opposing end open to an external environment. In another embodiment, the covering cooperates with the free ink chamber groove to form a free ink chamber duct with one end open to the free ink chamber through hole and an opposing end open to the external environment.
In accordance with other embodiments, an ink cartridge cap is described that includes a substrate for mounting to an ink cartridge body to provide a substantially enclosed ink cartridge, the substrate including a first vent and a second vent providing fluid communication between a proximal side of the ink cartridge cap and a distal side of the ink cartridge cap, where the proximal side is intended to comprise an interior surface of an inkjet cartridge and the distal side is intended to comprise an exterior surface exposed to an external environment when mounted to the ink cartridge body, and where the second vent includes an ink fill port in communication with a labyrinth duct.
In another embodiment, the first vent includes an extended duct having a length to width ratio of 25:1 or larger, and the labyrinth duct includes a length to width ratio of 25:1 or larger, and the ink fill port has a diameter larger than a width of the labyrinth duct. In yet another more detailed embodiment, the invention further includes a covering overlaying a first groove within the substrate to form the extended duct, the extended duct and a first through hole forming a first extended channel that provides direct gaseous communication between proximal and distal sides of the substrate, the covering also overlaying a second groove within the substrate to form the labyrinth duct, the labyrinth duct and ink fill hole forming a second extended channel that provides direct gaseous communication between proximal and distal sides of the substrate.
In other embodiments, an ink cartridge is described that includes (a) an ink cartridge body including a floor and an exterior wall partially defining an interior volume, the ink cartridge body including a capillary producing medium; and (b) an ink cartridge cap mounted to the ink cartridge body to substantially enclose the interior volume, the ink cartridge cap including two vents in direct communication with the interior volume, wherein a first vent incorporates an ink supply port
In some embodiments, a method of venting a multi-chamber ink cartridge is described that includes the steps of (a) forming a first vent passage and a second vent passage in an ink cartridge lid; (b) mounting the ink cartridge lid to an ink cartridge body to form a multi-chamber ink cartridge having an interior ink supply region and an overflow region, the ink supply region including a capillary producing medium substantially occupying the ink supply region and in communication with the overflow region; (c) venting the ink supply region to an external environment using the first vent passage; and (d) orienting the second vent passage between the overflow region and the external environment.
In some embodiments, the method includes stopping the second vent passage to discontinue communication between the external environment and the free ink chamber. In still other embodiments, the method includes unstopping the second vent passage to allow communication between the external environment and the free ink chamber.
In some embodiments, a method of filling an ink reservoir with ink is described that includes (a) dispensing a predetermined volume of ink into an interior volume of an ink reservoir and into communication with a capillary producing material substantially occupying a supply chamber of the ink reservoir, the ink reservoir also including a reserve chamber in direct communication with the supply chamber; and (b) incorporating two vents into the ink reservoir, the first vent establishing a first vent passage between an external environment and the supply chamber, and the second vent establishing a second vent passage between the external environment and the reserve chamber.
In some embodiments, the method includes stopping the second vent when the predetermined volume of ink dispensed in the dispensing act is sufficient to substantially fill the supply chamber and the reserve chamber.
In some embodiments, a method of fabricating and filling ink cartridges is described that includes (a) fabricating a first ink cartridge using a first cartridge cap and a first cartridge body, the first ink cartridge including an interior volume, the first ink cartridge including a plurality of vents providing communication between the interior volume and an external environment; (b) dispensing a predetermined amount of ink into the interior volume of the first ink cartridge; (c) stopping at least one of the plurality of vents of the first ink cartridge; (d) fabricating a second ink cartridge using the first cartridge cap and a second cartridge body, the second ink cartridge including an interior volume, the second ink cartridge including a plurality of vents providing communication between the interior volume and the external environment; (e) dispensing a predetermined amount of ink into the interior volume of the second ink cartridge, where a percentage of the interior volume of the first ink cartridge occupied by liquid ink is greater than a percentage of the interior volume of the second ink cartridge
In some embodiments, the first ink cartridge includes two ink chambers in communication with one another, the second ink cartridge includes two ink chambers in communication with one another, the first cartridge cap includes a plurality of through holes, with at least two of the through holes in communication with a labyrinth duct, and each through hole in communication with a labyrinth duct comprises a vent.